The Mercury Language Reference Manual: Top

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1 Introduction
2 Syntax
- 2.1 Syntax overview
- 2.2 Character set
- 2.3 Whitespace
- 2.4 Comments
- 2.5 Line number directives
- 2.6 Variables
- 2.7 Names
- 2.8 Literals
- 2.9 Punctuation symbols
- 2.10 Operators
- 2.11 Terms
- 2.12 Items
3 Clauses
- 3.1 Overview of Mercury semantics
- 3.2 Goals
- 3.3 Expressions
- 3.4 State variables
- 3.5 Variable scoping
- 3.6 Implicit quantification
- 3.7 Elimination of double negation
- 3.8 Definite clause grammars
4 Types
- 4.1 Builtin types
  - 4.1.1 Primitive types
  - 4.1.2 Other builtin types
- 4.2 User-defined types
- 4.3 Predicate and function type declarations
- 4.4 Field access functions
- 4.5 The standard ordering
5 Modes
- 5.1 Insts, modes, and mode definitions
- 5.2 Predicate and function mode declarations
- 5.3 Constrained polymorphic modes
- 5.4 Different clauses for different modes
6 Unique modes
- 6.1 Destructive update
- 6.2 Backtrackable destructive update
- 6.3 Limitations of the current implementation
7 Determinism
- 7.1 Determinism categories
- 7.2 Determinism checking and inference
- 7.3 Replacing compile-time checking with run-time checking
- 7.4 Interfacing nondeterministic code with the real world
- 7.5 Committed choice nondeterminism
8 User-defined equality and comparison
9 Higher-order programming
- 9.1 Creating higher-order terms
- 9.2 Calling higher-order terms
- 9.3 Comparing higher-order terms
- 9.4 Higher-order insts and modes
  - 9.4.1 Default insts for functions
  - 9.4.2 Combined higher-order types and insts
10 Modules
- 10.1 The module system
- 10.2 An example module
- 10.3 Submodules
- 10.4 Module initialisation
- 10.5 Module finalisation
- 10.6 Module-local mutable variables
11 Type classes
- 11.1 Typeclass declarations
- 11.2 Instance declarations
- 11.3 Abstract typeclass declarations
- 11.4 Abstract instance declarations
- 11.5 Type class constraints on predicates and functions
- 11.6 Type class constraints on type class declarations
- 11.7 Type class constraints on instance declarations
- 11.8 Functional dependencies
12 Existential types
- 12.1 Existentially typed predicates and functions
- 12.2 Existential class constraints
- 12.3 Existentially typed data types
- 12.4 Some idioms using existentially quantified types
13 Type conversions
14 Exception handling
15 Formal semantics
16 Foreign language interface
- 16.1 Calling foreign code from Mercury
  - 16.1.1 pragma foreign_proc
  - 16.1.2 Foreign code attributes
- 16.2 Calling Mercury from foreign code
- 16.3 Data passing conventions
- 16.4 Using foreign types from Mercury
- 16.5 Using foreign enumerations in Mercury code
- 16.6 Using Mercury enumerations in foreign code
- 16.7 Adding foreign declarations
- 16.8 Declaring Mercury exports to other modules
- 16.9 Adding foreign definitions
- 16.10 Language specific bindings
17 Impurity declarations
- 17.1 Choosing the right level of purity
- 17.2 Purity ordering
- 17.3 Impurity semantics
- 17.4 Declaring impure functions and predicates
- 17.5 Marking a goal as impure
- 17.6 Promising that a predicate is pure
- 17.7 An example using impurity
- 17.8 Using impurity with higher-order code
18 Solver types
- 18.1 The ‘any’ inst
- 18.2 Abstract solver type declarations
- 18.3 Solver type definitions
- 18.4 Implementing solver types
- 18.5 Solver types and negated contexts
19 Trace goals
20 Pragmas
- 20.1 Inlining
- 20.2 Type specialization
- 20.3 Obsolescence
- 20.4 No determinism warnings
- 20.5 No dead predicate warnings
- 20.6 Format calls
- 20.7 Source file name
- 20.8 Old pragma syntax
21 Implementation-dependent extensions
- 21.1 Fact tables
- 21.2 Tabled evaluation
- 21.3 Termination analysis
- 21.4 Feature sets
- 21.5 Trailing
22 Bibliography
- [1]
- [2]
- [3]
- [4]
- [5]

The Mercury Language Reference Manual

Table of Contents

The Mercury Language Reference Manual, version rotd-2024-12-21